Polarised magnetoluminescence of excitons in homoepitaxial GaN layers

Magnetic field studies of circularly polarised emission due to free and bou nd excitons in high quality homoepitaxial GaN layers are presented. The con ventional analysis of the band structure of the wurtzite-type symmetry allo wed us to determine both the signs and the values of the effective Lande g- factors for electrons and holes participating in the recombination of free excitons originating from Gamma(9) and Gamma(7) valence band components as well as for electrons and holes weakly bound to donor and acceptor centres. The magnetic field splitting scheme of the conduction and the valence band is examined. The fine structure of the excitonic emission is also discusse d.